21261033112066 has 32 divisors (see below), whose sum is σ = 35269274508480. Its totient is φ = 9531980040000.

The previous prime is 21261033112051. The next prime is 21261033112097. The reversal of 21261033112066 is 66021133016212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19181185 + ... + 20259316.

It is an arithmetic number, because the mean of its divisors is an integer number (1102164828390).

Almost surely, 2^{21261033112066} is an apocalyptic number.

21261033112066 is a deficient number, since it is larger than the sum of its proper divisors (14008241396414).

21261033112066 is a wasteful number, since it uses less digits than its factorization.

21261033112066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39440850.

The product of its (nonzero) digits is 15552, while the sum is 34.

Adding to 21261033112066 its reverse (66021133016212), we get a palindrome (87282166128278).

The spelling of 21261033112066 in words is "twenty-one trillion, two hundred sixty-one billion, thirty-three million, one hundred twelve thousand, sixty-six".